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The period of time leading to the first episode of schizophrenic psychosis is described as the prodrome, that refers to the early symptoms and signs that precede the characteristic manifestations of the acute, fully developed illness. The prodromal period of schizophrenia can last from weeks to years, and most frequently its duration is more than a year. Cameron (1938) was the first who studied the mean duration of untreated psychosis and reported that 32.4% of the patients experienced the first psychotic symptoms within 6 months of first admission for schizophrenia, 17.6% within 6 months to 2 years and 48.1% 2 years or more before first admission for schizophrenia. The clinical features of the prodrome are highly heterogeneous but the premorbid cognitive decline is a major feature. Studies have shown that elevated dopamine system activity might be evident in the prodrome and increases further with the development of psychosis. Moreover, abnormal dopamine synthesis might be associated with prefrontal dysfunction, linking these to neurocognitive impairment observed during this phase. Therefore, the psychotic prodrome is potentially important for the early diagnosis and management of psychotic disorders, detection of high-risk individuals and the overall prognosis. In order to identify these patients, diagnostic criteria have been developed, based on the presence of attenuated positive symptom criteria; brief limited intermitted psychotic symptoms, schizotypal personality or a first-degree relative with a psychotic disorder and significant decrease in functioning during one month. It has been reported that 40% of persons who met these criteria transitioned to full-blown psychosis within one-year period. A number of retrospective studies despite numerous of shortcomings indicated that identification of the prodrome in certain clinical populations is possible and that the earlier the interventions are given, the more effective they appear to be. However the interventions available, such as crisis oriented interventions, symptomatic treatment and close monitoring have raise important ethical issues. The data of follow up studies encourage the use of second-generation antipsychotics, however, the problem of false positives who were never at risk of psychosis is ever increasing and it seems that the presence of prodrome does not guarantee the development of a full blown psychosis. Many of persons meeting the prodromal criteria, suffer from nonpsychotic disorders and have significant social, vocational, and cognitive problems. The challenge is to identify the minority of patients who are on the way to schizophrenia, as they might very well respond to early interventions. Several aspects that need to be carefully considered are the nature of symptoms, the degree of impairment, the side effects of pharmacological interventions, and also the stigma associated with prodrome of schizophrenia.